The present invention relates to a joint for optical fiber, telecommunication, submarine cables. In particular, the present invention refers to a joint for optical fiber, telecommunication, submarine cables of the type provided with a plastic material sheath and in which the sole mechanically resistant armor which is provided occupies the radially innermost zone of the cables themselves.
By means of the joints according to the invention, it is possible to connect, for example, the cables described in my copending U.S. application, Ser. Nos. 831,650 and 831,998 filed on Feb. 20, 1986 and entitled, respectively, "Pressure Resistant Submarine Optical Fiber Cable" and "Pressure Resistant Optical Fiber Cable" which illustrate cables of the type previously mentioned.
Joints for optical fiber submarine cables require great care in their making and construction. In fact, they have to provide perfect connections between the optical fiber ends, in addition to protecting the fibers and their connections from suffering very small mechanical stresses under the action of the hydrostatic pressure and under the tension stresses applied to the cable during its laying.
Therefore, it is important that the joints have a structure which, in addition to protecting the optical fibers, facilitates to the greatest extent the connections between the fibers. Further, it is important that the presence of the joints do not cause problems during the laying operations of a submarine cable including said joints.
In order to reduce these problems, it is necessary that the following conditions will be met:
(1) the outer dimensions of the outer diameter of the joints must be substantially equal to the outer dimensions of the diameter of the cable lengths connected by said joints; PA1 (2) the flexibility of the joints must differ from that of the cable lengths connected by said joints as little as possible; and PA1 (3) the weight of the joint must be kept, to the minimum.
Moreover, it is important that the sheath of the joints does not suffer damage due to a greater thermal expansion of the elements contained therein, for example, due to sun exposure while awaiting their laying, the materials forming the sheath being different from the materials of the elements enclosed by the sheath.